Ultraviolet curable silver composition and related method

Abstract

A photocurable silver composition is provided which comprises an ultraviolet light curable organic mixture, a photoinitiator, a silver powder, and a silver flake composition. The silver flake composition comprises at least 20% of the weight of the silver powder. The disclosed compositions may be used to produce silver-containing coatings on a variety of different substrates. Related methods are provided.

1 . A photocurable silver composition comprising: 
 an aliphatic acrylated urethane oligomer;    an acrylated epoxy oligomer; and    an acrylate monomer selected from the group consisting of non-bridged cyclic acrylate monomers, non-cyclic acrylate monomers, and mixtures thereof;    a photoinitiator;    silver powder; and    silver flakes in an amount of at least 20% relative to the weight of the silver powder.    
   
   
       2 . The silver composition of  claim 1  wherein the acrylate monomer is described by formula 1:  
     
       
         
         
             
             
         
       
     
     wherein R 1  is hydrogen or substituted or unsubstituted alkyl; and R 2  is non-cyclic functional group or a non-bridged cyclic group.  
   
   
       3 . The silver composition of  claim 2  wherein the acrylated monomer is a non-cyclic monomer and R 2  is a substituted or unsubstituted alkyl having more than 4 carbon atoms.  
   
   
       4 . The silver composition of  claim 2  wherein the acrylated monomer is a non-bridged cyclic acrylate monomer and R 2  is cycloalkyl, cycloalkenyl, or substituted or unsubstituted aryl.  
   
   
       5 . The silver composition of  claim 2  wherein R 1  is hydrogen or methyl.  
   
   
       6 . The silver composition of  claim 2  wherein R 2  is phenyl, benzyl, dicylcopentenyl, dicyclopentenyl oxyethyl, cyclohexyl, or naphthyl.  
   
   
       7 . The silver composition of  claim 1 , wherein the aliphatic acrylated urethane oligomer is present in an amount of about 3% to 8% of the silver composition.  
   
   
       8 . The silver composition of  claim 1 , wherein 
 the acrylated epoxy oligomer is present in an amount of about 2% to 4% of the silver composition;    the silver powder is present in an amount of about 50% to 60% of the silver composition;    the silver flakes are present in an amount of about 25% to 35% of the silver composition;    the aliphatic acrylated urethane oligomer is present in an amount of about 8% of the silver composition; and    the photoinitiator is present in an amount of about 3% to 6% of the silver composition.    
   
   
       9 . The silver composition of  claim 1  further comprising a component selected from the group consisting of a flow promoting agent, an adhesion promoter, a wetting agent, a conductive carbon black powder, an antimony tin oxide powder, and mixtures thereof.  
   
   
       10 . The silver composition of  claim 1  further comprising an antimony tin oxide powder and a flow promoting agent.  
   
   
       11 . The silver composition of  claim 10  further comprising a blend of a polyacrylic oligomer and an acrylate monomer.  
   
   
       12 . The silver composition of  claim 1  further comprising an isobornyl acrylate monomer.  
   
   
       13 . A photocurable silver composition comprising: 
 an aliphatic acrylated urethane oligomer;    an acrylated epoxy oligomer;    a photoinitiator;    a component selected from the group consisting of non-bridged cyclic acrylate monomers, non-cyclic acrylate monomers, and mixtures thereof; and    silver flakes in an amount of at least 20% relative to the weight of the silver powder.    
   
   
       14 . The silver composition of  claim 13  further comprising an isobornyl acrylate monomer.  
   
   
       15 . The silver composition of  claim 15  wherein the nonbridged cyclic acrylate monomers and the non-cyclic acrylate monomers are described by formula 1:  
     
       
         
         
             
             
         
       
     
     wherein R 1  is hydrogen or substituted or unsubstituted alkyl; and R 2  is non-cyclic functional group or a non-bridged cyclic group.  
   
   
       16 . The silver composition of  claim 15  wherein the acrylated monomer is a non-cyclic monomer and R 2  is a substituted or unsubstituted alkyl having more than 4 carbon atoms.  
   
   
       17 . The silver composition of  claim 15  wherein the acrylated monomer is a non-bridged cyclic acrylate monomer and R 2  is cycloalkyl, cycloalkenyl, or substituted or unsubstituted aryl.